Open Access. Powered by Scholars. Published by Universities.®
- Institution
- Publication
- Publication Type
Articles 1 - 6 of 6
Full-Text Articles in Engineering
Transmission Error Analysis And Avoidance For Ieee 802.15.4 Wireless Sensors On Rotating Structures, Jobin Jacob
Transmission Error Analysis And Avoidance For Ieee 802.15.4 Wireless Sensors On Rotating Structures, Jobin Jacob
All Theses
Wireless sensors are increasingly adopted in manufacturing and vehicular systems for monitoring critical components under continuous operation. Many such components move rapidly and frequently in metallic containments with challenging radio propagation characteristics.
For wireless sensors mounted on rotating structures, previous studies identified an eminent increase in packet transmission errors at higher rotation speeds. Such errors were found to occur at specific locations around the rotating spindle's periphery and such locations depended sensitively on sensor location and surrounding geometry. This thesis presents a systematic study of the expected packet error rates due to such errors, and analytically derives the first transmission …
Work In Progress -- Instrumentation On A Truss Adapted For Pre-College Outreach, Amy K. Perrey, Steve Eugene Watkins, Ralph E. Flori, Theresa M. Swift
Work In Progress -- Instrumentation On A Truss Adapted For Pre-College Outreach, Amy K. Perrey, Steve Eugene Watkins, Ralph E. Flori, Theresa M. Swift
Electrical and Computer Engineering Faculty Research & Creative Works
Engineering content is a valuable addition to pre-college instruction in science, technology, engineering, and mathematics (STEM) since it applies scientific concepts, illustrates scientific relevance and technology, and provides measurement opportunities. Also, complex systems and interactions can be shown. This work describes outreach resources using a seven-member instrumented truss apparatus. This aluminum bench-top model is scaled to support up to fifty pounds. Electrical resistance gauges are installed on several members for strain measurement. The resource set includes the truss apparatus, instrumentation, a PowerPoint presentation, and a background document. The pre-college objective is a set of demonstration resources for middle or high …
In-Plane Photonic Transduction Of Silicon-On-Insulator Microcantilevers, Ryan Anderson, Seunghyun Kim, Gregory P. Nordin, Jong Wook Noh, Jaime Cardenas
In-Plane Photonic Transduction Of Silicon-On-Insulator Microcantilevers, Ryan Anderson, Seunghyun Kim, Gregory P. Nordin, Jong Wook Noh, Jaime Cardenas
Faculty Publications
We demonstrate an in-plane photonic transduction method for microcantilevers, which have been widely investigated for sensor applications. In our approach the microcantilever is etched to form a single mode rib waveguide. Light propagates down the microcantilever and crosses a small gap at the free end of the microcantilever, some of which is captured by an asymmetrical multimode waveguide that terminates in a Y-branch. The Y-branch outputs are used to form a differential signal that is monotonically dependent on microcantilever deflection. The measured differential signal matches simulation when microcantilever rotation is properly accounted for. The measured differential signal sensitivity is 1.4 …
A Current-Sensorless Digital Controller For Active Power Factor Correction Control Based On Kalman Filters, Jonathan W. Kimball, Philip T. Krein
A Current-Sensorless Digital Controller For Active Power Factor Correction Control Based On Kalman Filters, Jonathan W. Kimball, Philip T. Krein
Electrical and Computer Engineering Faculty Research & Creative Works
For low-power AC-DC converters, power factor correction (PFC) can be accomplished simply with certain converters operating in discontinuous conduction mode (DCM). At higher power levels, DCM results in higher losses, so most PFC converters use current feedback to actively track the correct current waveshape. This work presents a way to provide PFC control without the current sensor, by replacing the sensor with a Kalman filter, which is essentially a stochastic observer. Experimental results verify its high power factor and low total harmonic distortion (THD).
Response Characterization Of Electroactive Polymers As Mechanical Sensors, G. Alici, Geoffrey M. Spinks, J. D. Madden, Y. Wu, G G. Wallace
Response Characterization Of Electroactive Polymers As Mechanical Sensors, G. Alici, Geoffrey M. Spinks, J. D. Madden, Y. Wu, G G. Wallace
Faculty of Engineering - Papers (Archive)
The characterization of the dynamic response (including transfer function identification) of trilayer polypyrrole (PPy) type conducting polymer sensors is presented. The sensor was built like a cantilever beam with the free end stimulated through a mechanical lever system, which provided displacement inputs. The voltage generated and current passing between the two outer PPy layers as a result of the input was measured to model the output/input behavior of the sensors based on their experimental current/displacement and voltage/displacement frequency responses. We specifically targeted the low-frequency behavior of the sensor as it is a relatively slowsystem. Experimental transfer function models were generated …
Gravimetric Chemical Sensor Based On The Direct Integration Of Swnts On Aln Contour-Mode Mems Resonators, Matteo Rinaldi, Chiara Zuniga, Nipun Sinha, Marzie Taheri, Samuel Khamis, Alan Johnson, Gianluca Piazza
Gravimetric Chemical Sensor Based On The Direct Integration Of Swnts On Aln Contour-Mode Mems Resonators, Matteo Rinaldi, Chiara Zuniga, Nipun Sinha, Marzie Taheri, Samuel Khamis, Alan Johnson, Gianluca Piazza
Matteo Rinaldi
This paper reports on the first demonstration of a gravimetric chemical sensor based on direct integration of Single Wall Carbon Nanotubes (SWNTs) grown by Chemical Vapor Deposition (CVD) on AlN Contour-Mode MicroElectroMechanical (MEMS) resonators. In this first prototype the ability of SWNTs to readily adsorb volatile organic chemicals has been combined with the capability of AlN Contour-Mode MEMS resonator to provide for different levels of sensitivity due to separate frequencies of operation on the same die. Two devices with resonance frequencies of 287 MHz and 442 MHz have been exposed to different concentrations of DMMP in the range from 80 …